40x40x20mm Super Strong Neodymium Block Magnet, N52 Permanent Magnet Disc, The World's Strongest and Most Powerful Rare Earth Magnets - One Piece

This is an interesting review because the number of stars for easy to remove and durability are both one. Normally, a one-star review is bad. But in this case, less starts is good news! Easy to remove would mean a weak magnet, and neodymium magnets are not durable. These are facts. The product advertisement on Amazon covers some of these points. But the question should have been "magnetic grip" and that would have been five stars. Complaining about a neodymium magnet being fragile is like saying an eggshell is fragile. It is the way it is.So, first off, you want powerful magnets? Order these. Good price, fast shipping, good product. You will get what you want. But there is more to the story.These are dangerous in even in experienced hands. I am experienced - and still had troubles. This is not the manufacturers or vendors fault. These are powerful magnets, and any difficulties are the responsibility of the user.Don't order these as toys. To avoid disappointment, you should know in advance exactly what you wish to do with these. I did know, and I had difficulties, because these magnets are so strong they are actually annoying!!I did not want multiple powerful magnets because of the need to avoid crashing magnets together which breaks them, creating sharp shards of metal, crushing fingers in the process. I knew I wanted a single magnet, to demonstrate the long distance effects of a powerful magnet.Other websites had what are probably better magnets at a similar price, but nobody could beat Amazon's shipping costs and time. So I bought four of these. They are shipped two to a small box, together, with a small spacer between them. I knew already I wanted these magnets stuck together into one big one. I knew I wanted to put them into a larger piece of metal to make handling easier and safer.When you order two, they come packed in the same box, separated by a piece of plastic and cushioned in styrofoam. Getting a magnet pair separated was difficult, but doable. I knew that bringing two pairs together in a controlled manner would be very difficult. Knowing that these magnets will accelerate towards each other in an instant, I put one pair outside the cardboard they shipped in, placed a magazine inside the box for extra spacing and cushioning, and brought them together. As expected, they flew together. But I could not move them enough to get the magazine out or slide them to the edge of the cardboard. The attractive force was so great the cardboard was compressed to nothing. I ended up cutting around the magnet outline, through the cardboard and the magazine.I decided to put the magnets into a vice, gripping the two lower magnets only. It took 20 minutes to get them properly oriented in the vice. Sliding and twisting the magnets required the use of a crowbar and vice grips. Using the bench vice and large water pump pliers, I was able to get enough separation to slide a wooden shim between them. Using the shim, I was able to get all the paper out between the magnet pairs, then slide the shim out, thus bringing the magnets together in a controlled fashion. This took another hour!I brought the four magnets into the house to tinker. From 18 inches away, a 3" diameter ceramic magnet, with a couple small disc magnets attached, slammed into my new big magnet. All three ceramic magnets broke and chipped my new big magnet. I was pretty confident 18" was enough separation.There is a very nice set of smart phone apps written by Keuwlsoft. Go to the play store, search for Keuwlsoft, scroll down and look for the "Gauss Meter." It is free, but you get ads. They are not bad, but I always buy the apps because I want to reward the creative minds that create these tools. The app turns the magnetometer inside your smartphone into a Gauss meter, allowing you to measure and quantify the intensity of magnetic fields. This Gauss meter picks up my new big magnet from a few feet away. Bringing the phone closer, hits the 45 gauss limit of the meter. It affects compasses and other magnets at a similar distance, which is exactly what I want to demonstrate to my students. 45 Gauss is a lot! The earths magnetic field average 1/2 a Gauss.Since I do not want to ever separate these magnets, I decided to put them into a protective metal sleeve. I used a 3" long piece of 2" x 2" x 1/8th" piece of square tubing. It was my intention to center the magnets in the tube by driving wooden wedges into place. The magnets had other ideas, and simply getting them into the tube required a hydraulic press. Driving a wedge between the magnet and the wall of the tubing was not possible, so I settled for putting wedges down the two remaining sides. See the photo.This magnet will serve my classroom demonstrations very nicely. The price is reasonable, shipping was free with Prime, and the two-day shipping time was fantastic. I urge you to pursue reading on magnet safety. Have fun, enjoy these, and be safe!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++..........................................................................................................................................................................+.3

I was lost at first thinking I wasted money since I wanted this to open a yondr pouch from school, I thought using only one by itself would work but it didnt since the pouches got stronger and thicker this year. Just keep both magnets together and it'll generate enough strength to open the pouch after you hit it a few times, you don't have to hit it crazy hard but it will open after a few good hits.

Ordered several timesAlways perfect. I cant test for magnetic quality, they are extremely strong though. Build quality is excellent.

CAUTION: I will still give these a 5-rating, because I do believe that they are every bit as strong as represented and a good value for what they are. However, every purchaser should be cautioned: if more that one magnet is used with another, you will need to be incredibly careful not to allow them to become closer than about 8”-12” to each other. If they are allowed to strike one another, you should expect one of or both to break, accompanied by a bright, startling spark. They are incredibly brittle. We experimented with our set for only 2 days before disposing of them for safety reasons. As for strength, they arrived separated by a plastic washer. Even so, they were very difficult to further separate using the instructed method of a table or counter edge. Without the washer it required most all of my strength to separate them.

Super strong magnets, very nice design however they are a little fragile for construction.

My teenage son has an interest in magnets. I bought these, knowing they weren't a toy, and made sure he understood to be careful, not to use near electronics, not to let them smash together, etc.Well, he managed to get them apart...... aaaaaaaaand they immediately smashed together and broke into a million chunks.Put the pieces into several containers before they went in the dumpster (otherwise they'd become part of the metal dumpster...)Still giving it 5 stars because they are exactly as advertised. These are EXTREMELY POWERFUL magnets. Once they are apart it not easy to keep them from smashing into each other. After they break, the pieces can have extremely sharp edges as well. These are very dangerous if not handled properly and are definitely not a toy for children. Or my teenager.If you need two, stupidly strong magnets for some reason, these will certainly do the trick.

For a magnet that is supposed to be incredibly strong they are very thin and weak!! My 11 yr old had just opened them up for his birthday and within 30 minutes they came together from 2 foot apart from each other and broke completely apart when they hit each other! 😭 They were just a brittle piece of metal inside of them, and didn't seem real?? They made a large flash of fire and sparks when they exploded??? In my 63 yrs I've never seen anything do that magnet wise for sure?? Not sure if these are kid rated??

super strong and powerful magnets… be careful because they will definetely chip each other from colliding even at short distances. these magnets will unlock anything that requires a magnet to unlock.